Multiple position adjusting device



April 21, 1953 E. HANSON EI'AL 2,635,573

MULTIPLE POSITION- ADJUSTING DEVICE Filed Jan. 5. 1951 2 SHEETS-SHEET 1 ERICK L. HANSON JOSEPH BARNA BY n M44414- Arron/7 April 21, 1953 E. L. HANSON ETAL MULTIPLE POSITION ADJUSTING DEVICE 2 SHEETS-SHEET 2 Filed Jan. 3. 1951 INVENTORS ERICK L. HANSON JOSEPH BARNA ATTORNEY FIGS- Patented Apr. 21, 1953 MULTIPLE POSITION ADJUSTING DEVICE Erick L. Hanson and Joseph Barna, Red Bank, N. J assignors to the United States of America as represented by the Secretary of the Army Application January 3, 1951, Serial No. 204,256

8 Claims. (01. 116-1241) (Granted under Title 35, U. S. Code (1952),

see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

This invention relates to a multiple position adjusting device such as may be used in selecting a desired frequency in a radio tuning unit.

The principles of the invention, however, may be adapted to a wide variety of uses such, for instance, as a dividing head for use in connection with machine tools, or other precision applications.

The invention fulfills a very important requirement in many types of apparatus wherein it is desired to select a large number of angular positions, each one with a high degree of precision and, moreover, the invention provides a positive interlocking means to hold a selected position and to provide for returning to that position or any other desired position with a maximum of precision.

An object of the invention is to provide a multi-position selecting device having positive positioning means.

A further object of the invention is to provide a positioning device in which selection of the desired position is greatly facilitated.

A further object of the invention resides in the durability of its construction which maintains its initial accuracy over a longperiod of use.

A still further object of the invention is to provide a positioning device in which a selected position is established by precision interlocking elements which permit no relative movement of the parts; such accuracy being readily attained independently of the skill of the operator.

Other objects and features of the invention will more fully appear from the following description taken in connection with the accompanying drawings and will be particularly pointed out in the claims. i

To present a better understanding of the invention a particular embodiment thereof will be described and illustrated in the drawings in which Fig. 1 is a front elevation of a device embodying the invention; Fig. 2 is a partial crosssection taken on line 2-2 of Fig. 3; Fig. 3 is a rear elevation of the device having portions broken away; Fig. 4 is a detailed viewv showing a portion of the position selecting means; Fig. 5 is a detailed View showing the interlock position of the locking means when a selected position has been established; and Fig. 6 is an enlarged sectional ,view through a detent guiding unit taken on line 66 of Fig. 5.

The embodiment of the invention illustrated provides a pair of manually operable coaxial dials bearing respectively fine and coarse peripheral divisions. To the former of these dials is secured a rotatable disc having notches corresponding to the dial divisions. A second dial which is independently operable has secured thereto a disc having a cam-like notch in itsperiphery. By rotating the second dial the cam notch may be positioned at a selected point in radial alignment with one of a plurality of detent plungers which are spring loaded to be moved radially inward and are guided in a fixed frame member.

The circumferential position of each .plunger is offset from an equal angular separation from its neighbor by an amount equal to a, uniform fractional portion of the distance between successive notches on the disc connected to the first mentioned dial. This arrangement of plungers provides means to select a desired position at a fraction of the distance between the divisions represented by the said notches.

The manner of operation of the device will be fully set forth hereinafter.

The form of the invention illustrated is provided with a pair of concentric manually operable dials; a dial l which will hereinafter be called the tens dial and a dial 2 to be called hereinafter a units dial. The dial I has an operating knob 21 of die cast metal or other suitable material. The dials are mounted for rotation within a frame member 3 made of any suitable material such as an accurately machinable metal. The frame 3 desirably is provided with a relatively flat front Wall and an upstanding peripheral flange 4. This construction presents a chamber or recess within which the active elements of the position selecting mechanism are received. 1

The frame 3 may be mounted in anysuitable manner such as upon a panel 5 or other support by means of a plurality of screws 6. The panel 5 is provided with a suitable aperture through which the operating shafts of the dials extend. The frame 3 is provided with a plurality of detent plungers l having radial movement with respect to the axis of the dials. Any convenient number of such plungers may be used such as the ten plungers selected for use in connection with the present embodiment of the invention. The plungers extend through the flange 4 and engage control discs, to be described hereinafter, situated within the aforementioned chamber in the frame 3. The plungers 1 are identical and move in radial apertures extending outwardly from the fiange 4. Desirably the plungers I are substantially square in cross-section and move in square apertures within their respective bosses which have been machined to receive the plungers with a minimum of side play. Any suitable means, however, may be employed to guide the plungers radially and prevent their axial rotation.

Each plunger is forced inwardly by a spring 8, one end of which is received Within a chamber formed in the plunger while its other end engages a closure member 9 fitting over the outer end of the bosses. The closure member may conveniently be made in the form of a cap which has screw threaded engagement with the outer end of the plungers guiding bosses. The inner end of each plunger is provided with a roller I rotatably mounted upon a pivot pin passing through the end of the plunger. The roller is received Within a slot in the end of the plunger situated between a pair of aligned detents II and I2. While the detents may be of conventional construction, a more suitable construction, however, provides that one active face of the detent be disposed radially to the axis of the device and its other side being disposed at an angle to said radial disposition thereby to produce an inwardly convergent wedge shaped detent.

When a plunger is in its innermost position, its detent II is received in a complementary notch formed in the periphery of a fixed disc 53 secured to the frame 3 in engagement with a front wall thereof as shown in Figs. 2 and 3. The disc I3 serves to position and lock the plungers in a predetermined position, the accuracy of which depends only upon the precision in the manufacture of the disc and its coacting detent.

The other detent I2 coacts with a disc It to be called the tens disc. This disc is secured to a shaft Iii journaled in a hollow concentric shaft I6 which in turn is journaled in the frame 3. Both of these shafts extend beyond the outer face of the panel 5. The projection of shaft I5 has secured thereto the dial I while the extension of the shaft I6 has the dial 2 secured thereto.

The shaft I6 has secured thereto another disc IT to be called the detent control disc. The disc I! is situated closely adjacent to and freely movable between the stationary disc I3 and the movable disc I4. The disc I'I also lies in the plane of the rollers IE! on the plunger-s I. The disc I! is generally circular in form, its periphery being concentric to its shaft and situated to engage the rolls I!) thereby normally acting to hold the plungers in their retracted position. The disc, however, has a cam-like depression IS in its periphery. By rotation of the dial 2 the depression I3 may be presented selectively to any one of the plungers I thereby releasing the selected plunger for inward movement. However, the selected plunger may still be held in outward position by engagement of its detent I2 with the peripheral portion of the tens disc Ill.

The disc I 4 is provided with a plurality of notches I9 equally spaced around its periphery. In the particular embodiment shown there are 36 such slots which correspond to the divisions shown on the tens dial I. v

The slots I9 desirably have the same contour as those in the plate I3 and by coacting with the detents I2 serve to lock the disc It in a desired position in a manner to be set forth hereinafter.

The shaft I5 desirably is reduced in diameter at its inner end. The reduced diameter passes through a bearing in a cover plate which in turn is secured to the frame 3. The cover plate serves not only to support the shaft but to exclude foreign matter from the mechanism within and when removed provides access to the mechanism. The shaft I5 is extended beyond the cover plate presenting a portion 2l' to which may be secured the shaft of a variable capacitance, reactance or any device requiring the accurate determination of a plurality of angular positions such, for example, as a dividing head.

A refinement in the adjustability of the dial 2 may be provided by a click stop means. Such a means may consist of a steel ball 22 yieldingly received in a recess in the frame 3. The ball 22 is urged into contact with the disc I! by means of a spring or its equivalent. The disc I! is provided with a plurality of spot recesses 23. The position of the recesses are concentric with the axis of the disc and are spaced from each other in such manner that at each of the 10 positions of the dial 2 the ball 22 will enter a recess in the disc H.

To enable the operator of the device to properly adjust the dials a reference point 25 is provided at a convenient point adjacent to the per ph y of the dial 2.

The invention functions generally upon the principles of the Vernier, that is, a first position is established which represents a particular digit or digits in the number representing the desired position and subsequently by operating another adjusting means, a final determination is obtained. This final determination establishes the true desired setting of the device and rep resents the position designated by the first two and the last digit of the number representing the final position of the shaft I5.

To operate the device all of the detent plungers must first be retracted. This is accomplished together with the first adjusting step b rotating the units dial 2 until the reference mark 24 is between two of the divisions thereon, one of which bears the number of the last digit in the number representing the desired position and the other division bears the next lower number. For example, if the last number of the desired combination of numbers is 6, the dial is set between 5 and 6.

The tens dial is now free to rotate and is set at the position represented by the first two digits of the desired number. For example, if the number desired was 226 the tens dial would be set at 22. The units dial is then moved to the 6th position because 6 is the last digit in the required number. This adjustment releases the correct plunger so that it can subsequently have further movement. The final step is accomplished by rotating the tens dial a short distance clockwise until the detent I2 in the number 6 position interlocks with the appropriate notch in the tens dial. This position will therefore be m of the distance from the number 22 toward the number 23 on the tens dial and is accurately established by the predetermined fixed position of the number 6 plunger. This position is further fixed with precision by the engagement of the detent II upon the plunger with its cooperating notch in the fixed units plate I3.

A valuable precision factor of the invention resides in the conformation of the notches in the discs I3 and I4 and their cooperating detents. Their radially disposed sides 25 are capable of being accurately machined to a high degree of precision and since it is obvious that the sides 25 act to finally determine the position of the shaft 2|,

a desired position can be established with great accuracy. The cooperating angular faces 26 of the slots serve to lock the detents in the slots and serve to eliminate all relative motion between the detents and the disc M. It will be apparent, however, that the precision of the position of the angular faces 26 is not highly critical, the final position as above stated being determined by the radial faces 25, despite any slight mismatch of the angular faces of the slots and the cooperating detents. The over-all accuracy of the device is thus greatly enhanced by such construction.

What is claimed is:

1. A multiple position adjusting device comprising a movable member, indexing means on said member having positive action interlocking stations uniformly spaced thereon, a fixed reference point, a visible divided scale operable to present a selected one of said stations to said reference point thereby establishing a first position, means to lock said movable member in a second fixed selected position including a plurality of inter-engaging means each positioned to interlock with one of said stations at a different predetermined measured, fractional part of the distance between successive stations and means to select one of said interlocking means to inter-engage with a station on said indexing means at said first position or at a selected point a predetermined measured fraction of the distance between successive stations away from the first selected position.

2. A multiple position adjusting device comprising an adjustable member, indexing means on said member having a plurality of uniformly spaced notches, a reference position, a visible divided scale to present a selected notch to said reference position to establish a first position, means to lock said movable member in a second selected position including a plurality of interlocking members each positioned to index said movable member to a predetermined fractional distance between adjacent notches, and separate means to select one of said interlocking members to interlock with a notch at a desired fractional distance between notches away from said first position.

3. A rotating multiple position adjusting device comprising a shaft to be positioned, indexing means on said shaft having a plurality of uniformly spaced notches, a reference position, a plurality of fixed position detents arranged'to engage said notches, said detents being spaced non-uniformly their sequential difference in spacing being the sum of uniform fractional parts of the distance between said notches, means to move said shaft to present a selected notch to said reference position to establish a first position, and separate means operable selectively to release one of said detents to engage a notch in said index member thereby to establish a desired final fractional position between consecutive notches away from said first position.

4. A multiple position adjusting device comprising a rotatable shaft, indexing means on said shaft having a plurality of equally spaced positive action indexing stations. a dial on said shaft having divisions corresponding to those of said index stations, a fixed reference position, means to rotate said shaft to present a selected index station to said reference position thereby establishing a first position, a plurality of detents having fixed angular positions with respect to the axis of said shaft arranged to interlock with the stations on said indexing means said detents being spaced non-uniformly their sequential difference in spacing being the sum of uniform fractional parts of the angle between the adjacent indexing stations, a rotatable detent control normally acting to hold said detents inactive and having means selectively to render active one detent at a time thereby to lock said shaft in final position a selected fraction of the distance between notches away from said first position, depending upon the selected angular position of said detent control member and a second dial connected to said detent control member and having divisions thereon to facilitate the activation of a desired detent.

5. A multiple position adjusting device comprising a main shaft to be positioned, a frame within which said shaft is journaled, indexing means secured to said shaft having equally spaced notches therein, a dial for operating said shaft having a scale corresponding to the position of said notches, a plurality of inwardly movable detents arranged in fixed angular position about the periphery of said indexing means and angularly spaced from each other a non-uniform degree their sequential difference in spacing being the sum of uniform fractional parts of the angle between adjacent notches, a hollow shaft independently rotatable upon said main shaft, :3. detent control secured to said hollow shaft normally holding said detents inactive and having means selectively to render active one detent at a time, and a dial connected to said hollow shaft having a scale thereon corresponding to the positions of said detents.

6. A multiple position adjusting device having the elements defined in claim 3 in which the sides of said notches have one face which is radially disposed and a cooperating face disposed at an angle thereto.

7. A multiple position adjusting device having the elements defined in claim 4 and in which the said detent control comprises a, disc presenting a concentric peripheral edge for engaging and maintaining said detents inactive and a cutaway portion in its periphery of a size to activate only one detent at a time.

8. A multiple position adjusting device having the elements defined in claim 3 together with added interlocking means operable when said detents are engaging a notch to lock said detents in immovable position.

ERICK L. HANSON. JOSEPH BARNA.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,069,627 Schwarzhaupt Feb. 2, 1937 2,184,965 Villem Dec. 26, 1939 

